Table 2.
Effect size and p-values for group comparisons of individual measures: cross-sectional data.
| Measure (mean FA and Fsum of the statistically significant voxels in the TBSS analysis, cortical thickness of the precentral area, CSA at C2, and FA in CST at C2) | Effect size (Cohen’s d) | P-value: two-sample t-test for group difference | Corrected p-value (Bonferroni-Holm) | Low UMN score (< 3) ALS participants vs. controls (corrected p-value) | LMN predominant ALS vs. controls (corrected p-value) |
|---|---|---|---|---|---|
| Brain FA | 2.20 | 3 × 10−8* | 1.5 × 10−7* | 1.4 × 10−3* | 1.4 × 10−8* |
| Brain Fsum | 1.43 | 6 × 10−5* | 2.4 × 10−4* | 6.5 × 10−2 | 2.5 × 10−5* |
| Precentral cortical thickness | 1.35 | 1.3 × 10−4* | 3.9 × 10−4* | 4.4 × 10−2* | 3.3 × 10−3* |
| Spinal cord CST FA at C2 | 1.00 | 3.2 × 10−3* | 3.2 × 10−3* | 4.4 × 10−2* | 1.7 × 10−1 |
| Spinal cord CSA at C2 | 1.29 | 2.3 × 10−4* | 4.6 × 10−4* | 9.1 × 10−3* | 6.4 × 10−2 |
*p-value < 0.05 (ALS Amyotrophic lateral sclerosis, FA Fractional anisotropy, Fsum Sum of fiber volume fractions, CST Corticospinal tract, C2 Spinal cord C2 level, CSA Cross-sectional area, UMN Upper motor neuron, LMN Upper motor neuron).